Mastic, a resin produced from mastic trees on the island of Chios, the first natural chewing gum in the world, has been harvested in Greece for at least 2500 years.
Mastic is used as a flavouring for many sweets, famously known for Mastiha, digestive liquor from Chios.
The resin, dries into brittle, translucent droplets on tree trunks, resembling tears. This caused Hippocrates, the father of medicine, who used mastic for digestive problems, colds and as a breath freshener, to be the first to refer to mastic droplets, as "Tears of Chios".
When chewed, the resin softens and at first has a bitter taste, however, the more you chew, the more bitterness becomes a fresh, pine flavour.